Right-click the cell that contains the field [Qty] , and click Add Total. This adds a sum of the quantity for each order to the totals row. In the empty cell to the left of Sum[Qty] , type the label  Order Total . You can add a background color to the totals row. Select the two sum cells and the label cell.
Ladder logic is the first in a series exploring different software programming methods how to choose the most appropriate model of computation based on system requirements and architecture. Future articles will cover textual, function block/data flow, state chart, and simulation and modeling methods.
ladder. n. 1. a portable framework of wood, metal, rope, etc, in the form of two long parallel members connected by several parallel rungs or steps fixed to them at right angles, for climbing up or down. 2. any hierarchy conceived of as having a series of ascending stages, levels, etc: the social ladder.